Name of the Week


Melanorivulus proximus. From: Costa, W.J.E.M. 2018. Three new species of the killifish genus Melanorivulus from the Rio Paraná Basin, central Brazilian Cerrado (Cyprinodontiformes, Aplocheilidae). Zoosystematics and Evolution. 94 (1) 2018, 17–27.

10 January 2018
Melanorivulus proximus Costa 2018

Today we celebrate the New Year with the first new fish species of 2018 —Melanorivulus proximus, a killifish (Aplocheilidae, some say Cynolebiidae) from the middle section of the Rio Aporé drainage, upper Rio Paraná Basin, of central Brazil. Its specific name is the Latin word for near or neighbor (and the root for the modern-day proximal and proximity), and refers to its distribution in the same drainage as M. scalaris. The two killies are, as the name suggests, neighbors.

The generic name Melanorivulus — comprising small killifishes inhabiting shallow streams draining South American savannas — was also coined by Costa, an expert on neotropical killifishes, in 2006. It was originally proposed as a subgenus of Rivulus but Costa elevated it to a full genus in 2011. The name is a combination of the Latin melania, black pigmentation on the skin, and the genus name Rivulus, and refers to the black margins of unpaired and pelvic fins, a condition then unique among congeners in Rivulus.

An average of 390 new fish species have been described each year between 1998 and 2016. Last year was above average. According to our friend Erwin Schraml, keeper of Welt der Fische / World of Fishes, 458 new species and subspecies were described in 2017, plus 31 new genus-level names, and two replacement names.

The top 5 families were:

  1. Cyprinidae (carps & minnows) … 50 new species
  2. Gobiidae (gobies) … 45 new species
  3. Characidae (tetras, etc.) … 33 new species
  4. Nemacheilidae (stone loaches) … 31 new species
  5. Loricariidae (armored suckermouth catfishes) … 29 new species

2018 has gotten off to a fast start. In addition to Melanorivulus proximus, 22 other new species have been described. And it’s only the 10th day of the year.

And we’re still catching up with new names proposed last year!

Happy New Year!

Satanoperca daemon. Photo © Radek Bednarczuk. Courtesy: Cichlid Room Companion.

3 January 2018
Satanoperca daemon (Heckel 1840)

For over 160 years, no one knew why the “eartheater” cichlids of South America had such demonic names. And then neotropical cichlid aquarist Wayne Leibel chanced upon a textbook in a college bookstore and found a clue that eventually led him to the answer, or at least a very plausible explanation.

The scientific names for these fishes reflect the local names the indigenous people of Brazil have given them. Heckel described Geophagus jurupari and G. daemon in 1840. He knew the locals called these fishes jurupari, which means “demon” in Tupí. A jurupari is a malignant spirit that lurks in the forest and squeezes the throats of children. “Daemon” is a translation of “jurapari.” Günther assigned the species to a new genus in 1862, which he called Satanoperca. Kullander & Ferreira kept the tradition going in 1988 when they described Satanoperca lilith, named for Lilith, a nocturnal female demon in Babylonian and Jewish folklore. (In Hebrew-language texts, the term lilith translates as “night creature” or “night monster.”)

But what’s the link between a forest demon and these harmless (to humans) cichlids?

Back to Leibel. As he recounted in a 2008 article in Tropical Fish Hobbyist, he was “obsessed” with clearing up that etymological association and felt cheated that Heckel did not provide the answer. He consulted a variety of South American ethnographies and compulsively checked the index of any and every book having to do with Amazonian exploration, but found nothing.

Then, while perusing the stacks of the Anthropology/Sociology section in a college bookstore, he saw two books entitled, respectively, Mythology of North America and Mythology of Mexico and Central America by John Bierhorst. Browsing through them, he noticed that Bierhost had written an earlier book called Mythology of South America (1988). Leibel ordered a copy. When it arrived, he found seven pages devoted to “Yurupari” (an alternate spelling).

Bierhorst relates the mythological tale of a child named Yurupari who was born without a mouth and couldn’t eat or speak. Nourished by tobacco smoke, he nevertheless attained the age of six in a single day. His body was covered with hair, like a monkey. Only his legs, arms, and head were human. “When at last his mouth was formed,” Bierhorst wrote, “he let loose a roar that could be heard all over the world.”

Quoting Bierhorst: “One day he followed some little boys who were going into the forest to gather wild fruit. The children had been forbidden to eat this fruit, and when they broke the prohibition, Yurupari called down thunder and opened his mouth so wide that the children thought it was a cave. Running inside to protect themselves from the storm, they were eaten alive. Later, when he returned to the village, Yurupari vomited the three children, filling four baskets.”

Leibel had found his answer. Satanoperca are mouthbrooding fishes. Females collect fertilized eggs and hold them in their mouth. After hatching, the fry retreat to their mother’s mouth for protection.

“Clearly the native fishermen knew about the curious reproductive behaviors of geophagine cichlid fish well before science did!” Leibel wrote. “Just like the mythological Yurupari, parental Satonoperca ‘open [their] mouth so wide that the children [think] it is a cave’ and the fry swarm and dive deep into their throats for protection only to be spat out later, when the danger is past.”

Apparently, the natives were frightened by the fact that the young of these fishes were born from their mouths. They did not understand mouthbrooding and thus regarded it as the work of the devil.